In US, a new credit card issued by the Florida-based Stonegate Bank and available today will allow Americans to avoid the Cuban 10-percent penalty on the dollar. US citizens traveling to Havana can now do so without exchanging dollars, at a 10-percent fee, into the Cuban peso. Stonegate, the first US bank to introduce a debit card for use in Cuba, has issued a credit card as well. The bank announced yesterday that US travelers will be able to use its Mastercard to charge purchases at Cuban state-run businesses and some private businesses, starting June 15th.